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RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011

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Page 1: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

RECOGNIZING AND MANAGING

BOTTLENECKS

IN PROCESS PLANTS

Peter L. King

Lean Dynamics, LLC

October 2011

Page 2: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

Definition of a bottleneck

Bottlenecks in process plants

Capacity Constraint Resources (CCRs)

Finding the bottleneck ~ Value Stream Mapping

Root causes of bottlenecks

Bottleneck management ~ Theory of Constraints

Bottlenecks can move!

Successive bottlenecks

Additional examples

2

AGENDA

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Page 3: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

3 © 2010 - LEAN DYNAMICS LLC - ALLRIGHTS RESERVED

BOTTLENECK DEFINITION

Any resource where capacity is less than or equal to Takt (rate)

Any resource whose capacity is less than or equal to the

demand place upon it

Any process step with a utilization of 100% or greater

The process step with the lowest capacity

Page 4: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

4

WHY BOTTLENECKS REQUIRE ATTENTION

A primary objective of Lean is to achieve smooth continuous flow

Bottlenecks restrict flow

Bottlenecks cause inventory

Bottleneck management requires more inventory

A bottleneck may prevent you from making Takt

Thus bottlenecks must be identified

and opened up as much as practical

And bottlenecks must be very well managed

-->

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Page 5: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

5 © 2010 - LEAN DYNAMICS LLC - ALLRIGHTS RESERVED

BOTTLENECKS IN

PROCESS PLANTS

Page 6: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

6

BOTTLENECKS IN PROCESS PLANTS

In parts manufacture and assembly processes –

people are often the limiting factor

So managing bottlenecks focuses on people

Appropriate staffing

Task leveling

Judicious use of overtime, extra shifts

In most process plants, throughput is limited by equipment -

not by people

So managing bottlenecks becomes optimization of the

performance of the bottleneck step

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Page 7: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

7

BOTTLENECKS IN PROCESS PLANTS

Examples of process bottlenecks

Paper making – lineal speed of the web processing equipment

Paint manufacture – resin production batch time

Synthetic fiber manufacturing – threadline windup speed or

meter pump capacity

Batch chemicals – reaction time

Synthetic rubber – chemical reaction time, extrusion rates

Additional labor or overtime won’t help

Most plants are run 24 x 7, so running additional shifts is not

an option

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Page 8: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

8

CAPACITY CONSTRAINTS

Throughput can be limited by equipment design, by the inherent

capacity or a piece of process equipment

Throughput can be limited by a piece of equipment ‘s performance

Reliability issues

Yield losses

Changeover time

Throughput can also be limited by equipment scheduling, and by

how well flow is synchronized with other process steps

A Capacity Constraint Resource (CCR) is defined as:

Any resource which, if not properly scheduled and managed, is likely to cause

the actual flow of product through the plant to deviate from the planned flow.

Synchronous Manufacturing, Umble and Srikanth, 1990

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Page 9: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

CAPACITY CONSTRAINT IN CEREAL PLANT

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PACKAGING

STORAGE SILOS

SHAPE MANUFACTURING

FLAKE MANUFACTURING

Page 10: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

CAPACITY CONSTRAINT IN CEREAL PLANT

10 © 2010 - LEAN DYNAMICS LLC - ALLRIGHTS RESERVED

PACKAGING

STORAGE SILOS

SHAPE MANUFACTURING

FLAKE MANUFACTURING

The VSM shows the packaging area at 75% Utilization

Silos often fill up, so flake or shape production goes down

The culprit is poor scheduling, no synchronization

Any resource that has enough

effective capacity to meet customer

demand – but can’t because of poor scheduling – is

called a Capacity Constraint Resource

Page 11: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

DIAGNOSING THE BOTTLENECK

11 © 2010 - LEAN DYNAMICS LLC - ALLRIGHTS RESERVED

One of the best tools for finding the bottlenecks in your process is a

VALUE STREAM MAP

Page 12: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

CUSTOMER

SERVICE

REPS

ORDER

GRANTS

MATERIAL

RELEASES

SALES &

OPERATIONS

PLANNING

DEMAND

MANAGEMENT

PROCESS

CUSTOMER FORECASTS

(QUARTERLY)

ORDERS

PRODUCTION

SUPERVISOR

CAPACITY FORECAST

(MONTHLY)MASTER PRODUCTION

SCHEDULE (MONTHLY)

DAILY PRODUCTION

SCHEDULE (WEEKLY)

SCHEDULE UPDATES (DAILY)

AGGREGATED

DEMAND

(MONTHLY)

CURRENT

INVENTORIES

Frequency

Lot Size

1 Car/Day

140K lbs

Transp time 7 Days

Frequency

Lot Size

1.8 Cars/Day

140K lbs

Transp time 7 Days

SUPPLIER 1

SUPPLIER 2

SHEET

FORMING

(4)

SLITTING

(3)

CALENDARING

BONDING

(4)

CHOPPING

(3)

WRAPPING

PACKAGING

LABELING 5 546

6

Order Lead

Time

# SKUs

1 Week

4

Order Lead

Time

# SKUs

1 week

6

Invtry

Days

# SKUs

322M sq Ft

42

2,000

Invtry

Days

#

SKUs

4000

7

1000

Invtry

Days

#

SKUs

3650 R

21

200

Invtry

Days

#

SKUs

2500 R

12.6

50

Invtry

Days

#

SKUs

6.3M lbs

16

6

15 Min

16 Days

17 Min

12.6 Days 21 Days

10 Min

7 Days

10 Min

3 M

8 Min

42 Days

CUSTOMERS,

DISTRIBUTORS

Quantity/time

TAKT

230M Sq Ft/Mo

320K Sq Ft/Hr

Lead time Exp 7 Days

Frequency

Lot Size

12 Trucks/Day

648K Sq Ft

Transp time 3 Days

KEY

K = 1,000

M = 1,000,000

B = 1,000,000,000

NVA Time = 99 Days

VA Time = 73 Min

Effective

Capacity 11.8

9.5TAKT

Utilization 80%

15 MinLead time

Yield 87%

90%Reliability

UPtime 73.6%

50# SKUs

Batch size 1 roll

9 daysEPEI

C/O time 1 hr

2 RollsC/O loss

Avail time 168 hr/wk

3 x 8 x 7Shift schd

(Master Rolls/Hr)

Effective

Capacity 8.9

8.3TAKT

(Master Rolls/Hr)

Utilization 93%

17 MinLead time

Yield 87%

98%Reliability

UPtime 61%

200# SKUs

Batch size 1 roll

13 daysEPEI

C/O time 45 Min

~ 0C/O loss

Avail time 168 hr/wk

3 x 8 x 7Shift schd

Effective

Capacity 10.3

7.2TAKT

(Bonded Rolls/Hr)

Utilization 70%

10 MinLead time

Yield 98%

95%Reliability

UPtime 69%

1000# SKUs

Batch size 1 roll

7 daysEPEI

C/O time 5 Min

~ 0C/O loss

Avail time 168 hr/wk

3 x 8 x 7Shift schd

Effective

Capacity 29

24TAKT

Utilization 83%

10 MinLead time

Yield 100%

98%Reliability

UPtime 98%

1800# SKUs

Batch size 1 Slit Roll

7 daysEPEI

C/O time 0

0C/O loss

Avail time 168 hr/wk

3 x 8 x 7Shift schd

(Slit Rolls/Hr)

Effective

Capacity 200

120TAKT

Utilization 60%

8 MinLead time

Yield 100%

98%Reliability

UPtime 98%

2000# SKUs

Batch size 1 Cut Roll

7 daysEPEI

C/O time 0

0C/O loss

Avail time 168 hr/wk

3 x 8 x 7Shift schd

(Cut Rolls/Hr)

RAW MATERIAL

ORDERS (MONTHLY)

RAW MATERIAL

ORDERS (MONTHLY)

SCHEDULE UPDATES (DAILY)

Information Flow

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Material Flow

VSM COMPONENTS

Timeline

Data boxes

12

Page 13: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

© 2010 - LEAN DYNAMICS LLC - ALLRIGHTS RESERVED 13

Takt Time = Total available time / Customer demand

Takt Rate = Customer demand/ Available time

Example

A salad dressing line has weekly demand of 45,000 cases for the flavors

made on that line

Three eight-hour shifts per day, 5 days per week

Production continues through lunch, breaks, shift changes

Available time = 3 x 8 x 5 = 120 hours/week

Takt = 45,000 cases /120 hours = 375 cases/hour

So the plant must produce 375 cases per hour to satisfy customer

demand

VALUE STREAM MAP DATA

Page 14: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

© 2010 - LEAN DYNAMICS LLC - ALLRIGHTS RESERVED 14

Takt Rate = Customer demand/ Available time

The concept of Takt is that you want to synchronize your

throughput to Takt

You are meeting customer demand

With no overproduction

With minimal inventories

VALUE STREAM MAP DATA

Page 15: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

VALUE STREAM MAP DATA

Effective Capacity

It represents realistic expectations, not perfection

It should represent what we can realistically do today

15

Effective Capacity = Max Demonstrated Rate (MDR) x OEE

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If the salad dressing line could pack 500 cases/hour on a perfect

day

And OEE (or UPtime) is 85%

Then Effective Capacity is 425 cases/hour

Page 16: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

Utilization

A measure of how fully occupied a process step is, how busy it is

If our salad dressing line has an effective capacity of 425 cases/hour

Utilization = 375 cases per hour / 425 cases per hour

Utilization = 88%

Utilization is a good indication of how close to a

bottleneck any process step is

16

Utilization = Takt rate/ Effective capacity

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VALUE STREAM MAP DATA

Page 17: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

Cycle Time (Capacity) 30 BALES/SHFT

TAKT 35 BALES/SHFT

Utilization 117%

Lead Time 9.6 MIN

Yield 97%

Reliability 70%

Uptime 60%

# SKUs 14

Batch Size 1 BALE

EPEI 4 DAYS

C/O Time 45 MIN

C/O Losses 1%

Available Time 168 HRS/WK

Shift Sched 8 X 3 X 7

No of Operators 1

FIBER CUTTER/BALER

DIAGNOSING THE BOTTLENECK

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Root causes of bottlenecks can

be diagnosed from the data boxes

This is a B/N!

Machine failures are the primary

culprit

Changeover times also

contribute to the constraint (11%

of capacity)

Both must be improved to

resolve the B/N

Effective Capacity

Page 18: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

Cycle Time (Capacity) 50 GAL/MIN

TAKT 55 GAL/MIN

Utilization 110%

Lead Time 2 HR

Yield 97%

Reliability 98%

Uptime 74%

# SKUs 12

Batch Size 8000 GAL

EPEI 36 HR

C/O Time 40 MIN

C/O Losses 1%

Available Time 168 HR/WK

Shift Sched 12 hr X 2 sh X 7 d

No of Operators 1

RESIN REACTOR

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This is also a B/N!

Yield and reliability are not

the problem

Changeover times are the

issue here – 22% of the

available capacity is

consumed in C/Os

DIAGNOSING THE BOTTLENECK

Effective Capacity

Page 19: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

19 © 2010 - LEAN DYNAMICS LLC - ALLRIGHTS RESERVED

ROOT CAUSES OF BOTTLENECKS

Once a bottleneck has been identified, it is important to

understand why it is a bottleneck.

The most common causes in process plants:

Inherent equipment capacity limitations

Mechanical or electrical reliability problems

Yield losses

Long changeovers

Inappropriate scheduling or lack of synchronization (CCRs)

Page 20: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

TYPICAL BOTTLENECK ROOT CAUSES

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Based on a small sampling of VSMs from process plants

Data boxes of bottleneck or near-bottleneck resources were studied for

most significant root cause

When more than one reason contributed, partial weight was given to each

Disclaimer: this is not based on any

scientific, statistically valid study!

Page 21: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

21 © 2010 - LEAN DYNAMICS LLC - ALLRIGHTS RESERVED

MANAGING

THE

BOTTLENECK

Page 22: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

22 © 2010 - LEAN DYNAMICS LLC - ALLRIGHTS RESERVED

MANAGING THE BOTTLENECK

Once the bottleneck has been identified and its root cause(s)

determined, it’s time to open it up, to increase flow.

If that can’t be done, at least make sure the bottleneck is not

further constrained by limitations elsewhere in the process

Theory of Constraints is the best way to do this

Page 23: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

CONSTRAINT MANAGEMENT PROCESS

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Page 24: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

CONSTRAINT MANAGEMENT PROCESS

24

IDENTIFY THE BOTTLENECK

EXPLOIT THE BOTTLENECK

SUBORDINATE EVERYTHING TO THE BOTTLENECK

ELEVATE THE BOTTLENECK

CAPACITY

FIND THE NEXT BOTTLENECK AND

REPEAT

Theory of Constraints Eliyahu M. Goldratt, 1990

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Page 25: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

CONSTRAINT MANAGEMENT PROCESS

25 © 2010 - LEAN DYNAMICS LLC - ALLRIGHTS RESERVED

IDENTIFY THE

BOTTLENECK

EXPLOIT THE

BOTTLENECK

SUBORDINATE

EVERYTHING TO

THE BOTTLENECK

Look for inventory

Study the VSM

Mathematical analysis (Excel, FlexSim)

Make sure the B/N is running at max rates

Reduce changeover times - SMED

If CCR, improve flow synchronization

Don’t let the B/N be constrained by

upstream or downstream limitations

Theory of Constraints Eliyahu M. Goldratt, 1990

Page 26: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

PROCESS SYSTEM INTERACTIONS

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STEP

A

STEP

B

STEP

C

CAPACITY 100 GPM

50 GPMTAKT

UTILIZATION 50%

90%OEE

CAPACITY 48 GPM

50 GPMTAKT

UTILIZATION 104%

90%OEE

CAPACITY 100 GPM

50 GPMTAKT

UTILIZATION 50%

90%OEE

Where is the bottleneck?

What is the flow through the bottleneck?

48 GPM?

Wrong! The average flow is 39 GPM. (48 GPM x 90% x 90%)

The bottleneck resource suffers whenever there is an upstream or

downstream interruption

Page 27: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

B/N MANAGEMENT ~ THEORY OF CONSTRAINTS

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STEP

A

STEP

B

STEP

C

CAPACITY 100 GPM

50 GPMTAKT

UTILIZATION 50%

90%OEE

CAPACITY 48 GPM

50 GPMTAKT

UTILIZATION 104%

90%OEE

CAPACITY 100 GPM

50 GPMTAKT

UTILIZATION 50%

90%OEE

BUFFERINVENTORY

EMPTYBUFFER

Buffer inventories can alleviate the interaction

They can de-couple the various interruptions

They won’t eliminate the bottleneck

But they will prevent the bottleneck flow from being further

constrained

Page 28: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

B/N MANAGEMENT ~ THEORY OF CONSTRAINTS

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STEP

A

STEP

B

STEP

C

CAPACITY 100 GPM

50 GPMTAKT

UTILIZATION 50%

90%OEE

CAPACITY 48 GPM

50 GPMTAKT

UTILIZATION 104%

90%OEE

CAPACITY 100 GPM

50 GPMTAKT

UTILIZATION 50%

90%OEE

BUFFERINVENTORY

EMPTYBUFFER

This should be kept full to feed Step B when Step A is down

If max downtime duration on Step A is 2 hours….

Buffer should be ~ 5800 gallons

(2 hr x 60 min x 48 GPM)

This should be kept empty so that

there is a place to put material

from Step B while Step C is down

How large

should this

buffer be?

Page 29: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

CONSTRAINT MANAGEMENT PROCESS

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FIND THE NEXT

BOTTLENECK AND

REPEAT

ELEVATE THE

BOTTLENECK

CAPACITY

Increase the effective B/N capacity

Reduce Yield losses

Improve reliability – implement TPM

Increase ideal capacity – modify the

equipment

Once this B/N is no longer the B/N

Find the new B/N

There is usually a B/N!

Theory of Constraints Eliyahu M. Goldratt, 1990

Page 30: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

30 © 2010 - LEAN DYNAMICS LLC - ALLRIGHTS RESERVED

MOVING

BOTTLENECKS

Page 31: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

BOTTLENECKS CAN MOVE WITH PRODUCT MIX

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AVERAGE OF ALL PRODUCTS

6

SHEET

FORMING

1

1.5

BONDING

1

1.5

Invtry

Days

# SKUs

625 Rolls

12.6

8

Eff Cap 2.22

2.1TAKT

(Rolls/hr)

94%Utilization

Eff Cap 2.95

2.4TAKT

(Rolls/hr)

81%Utilization

The bottleneck may move as the process cycles through the various

products being made.

In his case, both forming and bonding have enough capacity to meet

customer demand

Page 32: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

PRODUCT-SPECIFIC BOTTLENECK

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PRODUCT 432A

6

SHEET

FORMING

1

1.5

BONDING

1

1.5

Invtry

Days

# SKUs

625 Rolls

12.6

8

Eff Cap 2.35

2.4TAKT

(Rolls/hr)

102%Utilization

Eff Cap 2.22

2.1TAKT

(Rolls/hr)

94%Utilization

When forming products with very high basis weight, forming must run

at slower lineal speeds - mass flow is the limiting factor

Thus forming becomes the bottleneck when making these products

Page 33: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

33 © 2010 - LEAN DYNAMICS LLC - ALLRIGHTS RESERVED

PRODUCT-SPECIFIC BOTTLENECK

PRODUCT 4516F

6

SHEET

FORMING

1

1.5

BONDING

1

1.5

Invtry

Days

# SKUs

625 Rolls

12.6

8

Eff Cap 2.95

2.4TAKT

(Rolls/hr)

81%Utilization

Eff Cap 1.9

2.1TAKT

(Rolls/hr)

110%Utilization

For products that must be bonded at higher temperature, the bonder

must run slower to allow more time in contact with the heated roll

So for these products, bonding becomes the bottleneck

Page 34: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

34 © 2010 - LEAN DYNAMICS LLC - ALLRIGHTS RESERVED

PRODUCT-SPECIFIC BOTTLENECK

Other examples:

Synthetic fiber production

Fiber winding is the B/N for very fine fibers

The metering pump is the B/N for thicker fibers

Salad dressing and ketchup bottling lines

For larger bottles, the bottle filler will be the B/N

For smaller bottles, the label applicator may be the B/N

For very small cartons for convenience stores, the carton

erector/filler may become the B/N

Page 35: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

35 © 2010 - LEAN DYNAMICS LLC - ALLRIGHTS RESERVED

WHY DOES THIS MATTER?

PRODUCT 4516F

Doesn’t it all average out over time?

Yes, but so does commuter traffic

and you see what can happen during rush hour!

PRODUCT 432A

6

SHEET

FORMING

1

1.5

BONDING

1

1.5

Invtry

Days

# SKUs

625 Rolls

12.6

8

Eff Cap 2.35

2.4TAKT

(Rolls/hr)

102%Utilization

Eff Cap 2.22

2.1TAKT

(Rolls/hr)

94%Utilization

6

SHEET

FORMING

1

1.5

BONDING

1

1.5

Invtry

Days

# SKUs

625 Rolls

12.6

8

Eff Cap 2.95

2.4TAKT

(Rolls/hr)

81%Utilization

Eff Cap 1.9

2.1TAKT

(Rolls/hr)

110%Utilization

Page 36: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

6

SHEET

FORMING

1

1.5

BONDING

1

1.5

Invtry

Days

# SKUs

625 Rolls

12.6

8

Eff Cap 2.35

2.4TAKT

(Rolls/hr)

102%Utilization

Eff Cap 2.22

2.1TAKT

(Rolls/hr)

94%Utilization

36 © 2010 - LEAN DYNAMICS LLC - ALLRIGHTS RESERVED

WHY DOES THIS MATTER?

The process runs at the rate of the slowest asset

So you can’t catch up – things don’t average out!

Buffering ala Theory of Constraints will minimize the consequences

of moving bottlenecks

You must understand all of the steps that can be B/Ns –

to make sure all buffers are in place

PRODUCT 432A

PRODUCT 4516F

6

SHEET

FORMING

1

1.5

BONDING

1

1.5

Invtry

Days

# SKUs

625 Rolls

12.6

8

Eff Cap 2.95

2.4TAKT

(Rolls/hr)

81%Utilization

Eff Cap 1.9

2.1TAKT

(Rolls/hr)

110%Utilization

Page 37: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

SUCCESSIVE BOTTLENECKS

37 © 2010 - LEAN DYNAMICS LLC - ALLRIGHTS RESERVED

Once the bottleneck has been opened, and is no longer a

bottleneck, don’t assume that the process can now make

Takt.

There may be other steps which are bottlenecks – this may have

been masked by the most obvious bottleneck

An accurate VSM would have brought this to light

However….. The primary bottleneck can restrict flow in a way that

masks restrictions at other steps

Or…… managers may be making assumptions about bottleneck

locations without benefit of a VSM

Page 38: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

EXAMPLE – SALAD DRESSING

38 © 2010 - LEAN DYNAMICS LLC - ALLRIGHTS RESERVED

The plant manager of a salad dressing production and bottling

facility wanted to increase throughput on a sold-out line from 300 BPM

to 400 BPM

He and the plant engineer believed (correctly) that the bottleneck

was in the bottle filling step – based on experience and intuition

The technical staff developed a new filling nozzle, which could fill at

the higher flow rate with no increase in pressure.

However, before fabricating a complete set of new nozzles, they

developed a VSM

Page 39: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

39 © 2010 - LEAN DYNAMICS LLC - ALLRIGHTS RESERVED

HOMOGENIZER

EFF CAPACITY 60 GPM

75 GPMTAKT

UTILIZATION 125%

90%OEE

WAREHOUSE

Salad Dressing

Bottle Filling Line

SURGE

TANK

BOTTLE

FILLING

MACHINE

EFF CAPACITY 300 Bot/Min

400 BPMTAKT

UTILIZATION 133%

85%OEE

BOTTLE

CAPPER

EFF CAPACITY 500 BPM

400 BPMTAKT

UTILIZATION 80%

94%OEE

ACCUMULATING

BOTTLE

CONVEYOR

BOTTLE

LABELER

EFF CAPACITY 360 BPM

400 BPMTAKT

UTILIZATION 111%

82%OEE

CASE

PACKER

EFF CAPACITY 33 cases.min

34 cases/minTAKT

UTILIZATION 101%

73%OEE

NOTE: All capacities and Takt are relative to 24 oz bottles,

which is the primary size run on his line

SHRINK

WRAP

TUNNEL

EFF CAPACITY 122 cases/min

34 cases/minTAKT

UTILIZATION 28%

90%OEE

CASE

PATTETIZER

EFF CAPACITY 100 cases/min

34 cases/minTAKT

UTILIZATION 34%

94%OEE

PALLET

STRETCH

WRAPPER

EFF CAPACITY 224 pallet/hr

26 pallet/hrTAKT

UTILIZATION 12%

92%OEE

PALLET

LABEL

PRINTER

APPLICATOR

EFF CAPACITY 170 pallet/hr

26 pallet/hrTAKT

UTILIZATION 15%

76%OEE

BN #1 BN #2 BN #3 BN #4

Current State VSM, with the higher Takt requirement

EXAMPLE – SALAD DRESSING

Page 40: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

EXAMPLE – SALAD DRESSING

40 © 2010 - LEAN DYNAMICS LLC - ALLRIGHTS RESERVED

The plant manager of a salad dressing production and bottling

facility wanted to increase throughput on a sold-out line from 300 BPM

to 400 BPM

He and the plant engineer believed (correctly) that the bottleneck

was in the bottle filling step – based on experience and intuition

The technical staff developed a new filling nozzle, which could fill at

the higher flow rate with no increase in pressure.

However, before fabricating a complete set of new nozzles, they

developed a VSM

This revealed three other steps which would become bottlenecks as

throughput approached 400 BPM

The new nozzles would increase the bottle filler to 400 BPM, but line

speed would only increase to 320BPM!

Page 41: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

41 © 2010 - LEAN DYNAMICS LLC - ALLRIGHTS RESERVED

The cost of fitting the bottle filler with new nozzles was easily

justifiable

However, the cost of eliminating all 4 potential bottlenecks

was not

The decision was made to build a new line to handle the

increased demand

This also provided additional capacity for future demand

growth

They ultimately would have gone that way

The VSM and bottleneck analysis got them to the right

decision much sooner

And avoided the cost of a set of stainless steel nozzles.

EXAMPLE – SALAD DRESSING

Page 42: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

Do you have any bottlenecks in your plant?

Is it clearly understood where they are?

How do you manage them?

42

BOTTLENECKS IN PROCESS PLANTS

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Page 43: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

MORE EXAMPLES OF

BOTTLENECKS

IN PROCESS PLANTS

1) Film slitters in a plastic film plant

2) Curing ovens in a electronics circuit board factory

Page 44: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

© 2010 - LEAN DYNAMICS LLC - ALLRIGHTS RESERVED 44

X-RAY FILM MANUFACTURING EQUIPMENT CONFIGURATION

Pouching, Boxing, Palletizing

MATERIA

L FLO

W

Coater 1 Coater 2 Coater 3 Coater 4

X-ray Casting Machine 1

X-ray Casting Machine 2

X-ray Casting Machine 3

Roll Slitting Machine 1

Roll Slitting Machine 2

Roll Slitting Machine 3

Chopper 1

Chopper 2

Chopper 3

Chopper 4

Chopper 5

Page 45: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

Theoretically each step should have more than enough capacity to

handle the throughput

Especially the slitters - Utilization is ~ 70%

But flow can’t match demand

The Value Stream Map showed the Slitter OEE to be 60%

Root causes

Slitters had low maintenance priority

TPM wasn’t being practiced

PMs weren’t being done

45

1 – FILM SLITTING

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Roll Slitting Machine 1

Roll Slitting Machine 2

Roll Slitting Machine 3 Is there a

bottleneck?

Page 46: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

Solution

Give slitters an equal priority for maintenance

Implement TPM

Result

Slitter Utilization > 85%

Slitters no longer a bottleneck

Flow matches demand

46

1 – FILM SLITTING

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Page 47: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

47

2 – CURING OVENS – ELECTRONIC SUBSTRATES

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SUBSTRATE PREPARATION

COPPER PREPARATION

LAMINATING & CUTTING

CURING OVENS

EDGE TRIM PACKAGING

UPPER LAYER

PREPARATION

OEE on the Laminator and Edge Trimmer is good, = 90%

But that means they are down 10% of the time each

Ovens (2) have a 12 hour curing cycle

Ovens are very much the bottleneck

Oven utilization ~ 100%

Next is the Laminator, at 75%

Page 48: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

48

2 – CURING OVENS – ELECTRONIC SUBSTRATES

© 2010 - LEAN DYNAMICS LLC - ALLRIGHTS RESERVED

SUBSTRATE PREPARATION

COPPER PREPARATION

LAMINATING & CUTTING

CURING OVENS

EDGE TRIM PACKAGING

UPPER LAYER

PREPARATION That won’t relieve the bottleneck

– it’s still the bottleneck

But at least it won’t suffer from Laminator or

Trimmer downtime

Solution – put buffers in front of

and after the Bottleneck

B B

Page 49: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

49

Bottlenecks matter!

They constrain material flow

They prevent you from meeting customer demand

They require inventory

Bottlenecks in process plants are usually the equipment, not staffing

Adding people won’t help, nor will overtime, extra shifts

So you must confront the root causes

Opening the bottleneck requires performance improvement

Yield improvement

Reliability improvement (TPM)

Changeover reduction (SMED)

Whenever there are bottlenecks, Theory of Constraints should be applied

Summary

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Page 50: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

TO LEARN MORE …..

The material in this presentation is featured in

Productivity Press

May 2009

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Page 51: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

Questions?

[email protected]

(302) 239-1667

(302) 528-2700

51 © 2010 - LEAN DYNAMICS LLC - ALLRIGHTS RESERVED

Page 52: RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS · RECOGNIZING AND MANAGING BOTTLENECKS IN PROCESS PLANTS Peter L. King Lean Dynamics, LLC October 2011 Definition of a bottleneck

Do you have any bottlenecks in your plant?

Is it clearly understood where they are?

How do you manage them?

52

BOTTLENECKS IN PROCESS PLANTS

© 2010 - LEAN DYNAMICS LLC - ALLRIGHTS RESERVED